Automatic governor for air-brake systems.



l No. 869,731.

PATENTED OCT. 29. 1907..

J. W. RICHARDSON.

A AU'IB/lATIC GOVERNOR EUR AIR BRAKE SYSTEMS.

APPLICATION FILED FEB. 5, 1907.

sweufoz Jasje/viz ZM H dm/daan UNITED STATES P'LTE'T oEEroE.

JOSEPH W. RICHARDSON, OF CUMBERLAND, MARYLAND, ASSIGNOR OF ONE-THIRD TOARUFUS E. WEIME'R, OF `TOHNSTOWN, PENNSYLVANIA.

Specification of Letters Patent.

Patented Oct. 29, 1907.

Application iiled February 5` 1907. Serial No. 365,859.

To all 'whom it may concern:

Be it known that l, .losnrn W. RICHARDSON, a citizen of the UnitedStates of America, residing at Cilinberland, in the county oi Alleganyand State of Maryland, have invented new and useful Improvements inAutomatic Governors for Air-Brake Systems, of which the following is aspecification.

This invention relates to automatic governors for air brake systems, andone of the principal objects of the saine is to provide reliable andefficient means formaintaining a predetermined pressure in the trainline relatively to the pressure in the main reservoir.

Another object of my invention is to provide an aulomatic governor forair brake systems which shall be simple in construction, composed ofcomparatively few parts, which cannot get readily out of order` andwhich will operate efiiciently under varying conditions.

Still another object of the invention is to provide a governor of thecharacter referred to` in which access may be readily had to theinterior of the governor' casing, and in which provision is made foradjustment to control tlre movement of the piston rod.

These and other objects may be attained by means of the constructionillustrated in the accompanying drawing in which the figure represents acentral vertical section taken thro ugh the governor.

Referring to the drawing ior a more particular description of myinventionj the numeral 1 designates a casing provided with a screw cap 2which closes one end of the casing, said cap being fitted to the casingby au airtight joint, and provided with an extending boss 3 which isinternally screw threaded. as at 4. to accommodate a set screw 5. saidset screw having a projecting end 6 and a squared portion 7 foraccommodation of a Wrench in adjusting said set screw. At the oppositeend of the casing 1 a threaded plug 8 is provided for giving access tothe interior of the casing at this end thereof. Inside the casing is achamber a and an enlarged chamber b. A piston rod c is mounted in thesechambers, said piston rod carrying a piston head 9 provided With packing10 and fitted within the chamber a in an air-tight marmer. Carried bythe piston c is an enlarged piston head 11, also provided with packing12. and fitted in the chamber b in an air-tight manner. The piston cisprovided with a projection 13 at one end, and at its opposite end with asimilar projection 14 which terminates in a conical valve head 15. Anopening 16 in the partition 17 in the casing communicates with an airpassage 18 extending out through the casing, as at 19, and the trainline pipe 20 is connected to this opening. A val '.'e seat 21 is formedin the partition 17 to accommodate the conical valve 15. The air passage18 extends upward through the casing, and-communi- Cates at its upperend 22 with the larger chamber b in the casing. A pipe leading to themain reservoir is connected to the casing and communicates with thesmaller chamber a, said pipe being designated 23. Perforated lugs 24formed on or secured to the casing 1 are provided ior supporting thegovernor in any suitable position for use. At a point intermediate thechambers a and b is an intermediate equalizing chamber d. provided Withan opening e which communicates with the outer atmosphere. It will beunderstood that the pipe 23 and the train line pipe 2() are connected tothe engineers equalizing discharge valve in the locomotive. and throughsaid discharge valve to the main reservoir and to the train line.

The operation of my invention may be described as follows: For thepurpose of illustration it may be supposed that there are one hundredpounds pressure per square inch in the main reservoir, and air from thisreservoir communicates through pipe 23 with chamber a, and this pressureraises the piston head 9, and the conical valve 15 to open the port 16to permit the air to flow to the train line pipe 20, and also to pass upthrough the passage 18, and discharge at 22 into the enlarged chamber babove the piston head 11.` Owing to the difference in area between thepiston head 11 and piston head 9, the pressure upon the top of thepiston 11 will force the valve 15 to its seat, thus seating valve 15 andclosing port 16, and thus maintaining a predetermined pressure in thetrain line dependent upon the relative sizes of the piston heads 9 and11. When the pressure in the train line is reduced either by leakage orby setting the brakes, the pressure in chamber a again raises the pistonhead 9 and opens communication between said chamber and the train line,and between said chamber and the chamber b through the passage 18 untilthe pressure in chamber b overcomes the pressure in chamber a owing tothe difference in area of piston head 1], and again closes the valve 15.

By adjusting the set screw 7, the throw of the piston rod c is regulatedto permit the valve head 15 to move relatively to its seat, more orless, to permit greater or lesser escape of air through the opening 16.The cap 2 can be remo ved from the casing and the plug 8 may also beremoved for the purpose of cleaning or repairs.

As shown in the drawing the relative sizes of the piston head 9 and 11will maintain a pressure of seventy pounds per square inch in the trainline, provided the main reservoir pressure is one hundred pounds persquare inch, but it will be obvious that any required difference inpercentage may be attained by regulating j the sizes of the piston headsto conform to the relative pressures desired.

Having thus described the invention, what I claim 1. A governor for airbrake systems comprising a casing provided with air chambers ofdifferent cross sectiona'r area, and an air passage extending into thebottom oi the casing :1nd cornnmnicnting with one ot' the chambers in.said cnsing, n piston provided with piston heads mounted to move insnid chzunhers, szlid,pistons having :i vnlve hezul thereon :ulnptct toengage :i vulve sent in :1n opening,r through said cnsin; whichcommunicates with said air passage, n train line pipe communicating withsaid air passage, and the latter communicating,r with the nir chamher0l? greater cross sectional aren to move the piston and sent the valveni'tcr pressure from the nmn reservoir unseats the vulve 2. A governorcomprising :i casing provided with chamhers of diierent cross-sectionalareas, and an intermediate balancing chamber open to the atmosphere, apiston mounted iu said casing and provided with heads fitting the innerwalls of said chambers, :t valve on the piston, 11 vulve seat in thecasing, a sc'rew cap fitting one end of the casing. n set screw mountedunderneath said cap, and adapted to he adjusted to limit the action ofsaid piston, and :1 plug tted to the opposite end of the casing to giveaccess to the valve seat, substantially as described.

In testimony whereof, I afx my signature in presence of two witnesses.

JOSEPH W. RICHARDSON.

Witnesses .TOHN L. FLETCHER, RUFUs E. WEIMER.

